This week, the ratings of 17 Oil Gas & Consumable Fuels stocks on Portfolio Grader are down. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

Slipping from a C to a D rating, NuStar Energy L.P. (NS) takes a hit this week. NuStar Energy L.P. transports and stores crude oil and refined products. The company also gets F’s in sales growth. For more information, get Portfolio Grader’s complete analysis of NS stock.

ConocoPhillips (COP) earns a F this week, moving down from last week’s grade of D. ConocoPhillips is an international company involved in the exploration, production, refining, and marketing of energy. The company also gets F’s in sales growth, operating margin growth, earnings surprise, and return on equity. For more information, get Portfolio Grader’s complete analysis of COP stock.

This week, Murphy Oil Corporation (MUR) drops from a C to a D rating. Murphy Oil Corporation is a worldwide oil and gas exploration and production company with refining and marketing operations in the United States and the United Kingdom. The company also gets F’s in sales growth, operating margin growth, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of MUR stock.

This week, Cheniere Energy Partners LP Holdings, LLC’s (CQH) rating worsens to a D from the company’s C rating a week ago. For more information, get Portfolio Grader’s complete analysis of CQH stock.

YPF SA Sponsored ADR Class D (YPF) is having a tough week. The company’s rating falls from a D to a F. YPF SA Sponsored ADR Class D is an energy company operating a fully integrated oil and gas chain with market positions across the domestic upstream and downstream segments. The company also gets F’s in earnings growth, earnings revisions, earnings surprise, earnings momentum, and free cash flow. For more information, get Portfolio Grader’s complete analysis of YPF stock.

This is a rough week for Memorial Resource Development Corp (MRD). The company’s rating falls to F from the previous week’s D. The company also gets F’s in operating margin growth, earnings surprise, earnings momentum, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of MRD stock.

Ship Finance International Limited (SFL) declines this week from a C to a D. Ship Finance International Limited is engaged mainly in the ownership and operation of vessels and offshore-related assets. The company also gets F’s in earnings revisions and free cash flow. For more information, get Portfolio Grader’s complete analysis of SFL stock.

Stone Energy Corporation (SGY) experiences a ratings drop this week, going from last week’s C to a D. Stone Energy Corporation is an independent oil and natural gas company engaged in the acquisition, exploration, exploitation, development and operation of oil and gas properties. The company also gets F’s in sales growth, earnings surprise, and free cash flow. For more information, get Portfolio Grader’s complete analysis of SGY stock.

Oasis Petroleum Inc. (OAS) gets weaker ratings this week as last week’s C drops to a D. Oasis Petroleum Inc. is an independant exploration and production company focused on the acquisition and development of unconventional oil and natural gas resources. The company also gets F’s in sales growth and operating margin growth. For more information, get Portfolio Grader’s complete analysis of OAS stock.

Mesa Royalty Trust’s (MTR) rating weakens this week, dropping to a D versus last week’s C. Mesa Royalty Trust holds royalty interests in oil and gas properties in the United States. The company also gets F’s in sales growth and earnings growth. For more information, get Portfolio Grader’s complete analysis of MTR stock.

Euronav NV (EURN) slips from a D to a F this week. The company also gets F’s in sales growth, earnings revisions, and earnings momentum. For more information, get Portfolio Grader’s complete analysis of EURN stock.

Ardmore Shipping Corp. (ASC) earns a F this week, moving down from last week’s grade of D. The company also gets F’s in earnings revisions, earnings momentum, and free cash flow. For more information, get Portfolio Grader’s complete analysis of ASC stock.

Teekay Offshore Partners L.P. (TOO) is having a tough week. The company’s rating falls from a D to a F. Teekay Offshore Partners L.P. provides marine transportation and storage services to the offshore oil industry. The company also gets F’s in operating margin growth, earnings growth, earnings revisions, earnings momentum, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of TOO stock.

This week, Baytex Energy Corp. (BTE) drops from a C to a D rating. Baytex Energy Corp. is focused on oil and gas production. The company also gets F’s in sales growth, earnings revisions, earnings surprise, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of BTE stock.

This is a rough week for Capital Product Partners LP (CPLP). The company’s rating falls to F from the previous week’s D. Capital Product Partners LP charters its vessels to be engaged in the seaborne transportation services of crude oil and refined petroleum products, edible oils, and soft chemicals. The company also gets F’s in earnings revisions and free cash flow. For more information, get Portfolio Grader’s complete analysis of CPLP stock.

GeoPark Ltd (GPRK) declines this week from a C to a D. The company also gets F’s in sales growth, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of GPRK stock.

Zion Oil and Gas, Inc. (ZN) slips from a C to a D this week. Zion Oil and Gas, Inc. operates as a development stage oil and gas exploration company in Israel. The company also gets F’s in return on equity and free cash flow. For more information, get Portfolio Grader’s complete analysis of ZN stock.

Louis Navellier’s proprietary Portfolio Grader stock ranking system assesses roughly 5,000 companies every week based on a number of fundamental and quantitative measures. Stocks are given a letter grade based on their results — with A being “strong buy,” and F being “strong sell.” Explore the tool here.